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采用三氧化二铁(Fe2O3)为铁源,抗坏血酸作碳源,通过在200℃下水热反应并经煅烧后合成出LiFePO4/C纳米复合材料.抗坏血酸在水热反应体系中不但作为最终反应产物的碳源,而且还起到了限制LiFePO4颗粒生长的作用.抗坏血酸的用量对产物的形貌、结构、碳含量有重要影响,进而影响产物的电化学性能.当抗坏血酸用量为1 g时,制得的LiFePO4/C纳米复合材料的粒径在220～280 nm.该材料用作锂离子电池的正极材料时,在0.1C的电流密度下循环500次后其放电容量仍保持159 mAh/g,并且具有较好的倍率性能.
LiFePO4 / C nanocomposites were synthesized by hydrothermal reaction at 200 ℃ and calcined at 200 ℃, using iron oxide (Fe2O3) as the iron source and ascorbic acid as the carbon source.Ascorbic acid was not only the final reaction product in the hydrothermal reaction system But also played a role in limiting the growth of LiFePO4 particles.The amount of ascorbic acid has an important influence on the morphology, structure and carbon content of the product, and further affect the electrochemical performance of the product.When the amount of ascorbic acid is 1 g, The particle size of LiFePO4 / C nanocomposites is in the range of 220-280 nm. When used as the positive electrode material for Li-ion batteries, the LiFePO4 / C nanocomposites have a discharge capacity of 159 mAh / g after 500 cycles at a current density of 0.1 C, Better rate performance.